Polycrystalline SrBi2Ta0.8Nb1.2O9 thin films

The growth, microstructure and micro-Raman properties of SrBi2Ta0.8Nb1.2O9 (SBTN) thin films deposited on Si(100) substrates using pulsed laser deposi tion (PLD) technique were studied at various substrate temperatures. Films were characterized using X-ray diffraction(XRD), atomic force microscopy(AF M), energy dispersive X-ray analysis (EDAX) and micro-Raman studies. AFM st udies indicated that the average grain size of the films increased between 0.08 mu m to 0.1 mu m with the increasing growth temperatures. Micro-Raman studies of SBTN films revealed the fact that shifting of Raman modes corres ponds to the BO6 (where B = Ta/Nb) octahedral symmetry, to higher frequenci es, is in accordance with the different masses of the B sire atoms and the force constants involved due to Nb doping at Ta sites.